Spraying device for spraying and fusing powdered material



June 5 1950 M. A. sANDoRA ETAL. 2,510,143

SPRAYING DEVICE FOR SPRAYING AND FUSING POWDERED MATERIAL Filed 001'.. 30, 1948 Patented June 6,n 1950 SPRAYING DEVICE FOR SPRAYING AND FUSING POWDERED MATERIAL Manuel A. Sandora, San Francisco, and CecilfE. Freeman, San Carlos, Calif., assignors to C. E. Freeman Co., Inc., San Francisco, Calif., a corporation Application October 30, 1948, Serial No. 57,584

4 Claims.

This invention relates to a spray gun of the type wherein a suspension of powdered, fusible material in compressed air is formed, and the Same is ejected from the gun together with a burning mixture of oxygen and combustible gas.

In spray guns of this character it is desirable to achieve an intimate mixture of combustible gas and oxygen, to maintain an even flow of materials, and to operate with the utmost economy of materials.

It is an object of the present invention to provide an improved type ofspray gun.

It is a particular object of the invention to provide a spray gun capable of ecient operation, a steady, smooth delivery of materials and economy of operation.

These and other objects of the invention will be apparent from the ensuing description and the appended claims.

One form which the invention may assume is exemplified in the following description and illustrated by way of example in the accompanying drawings in which:

Fig. 1 is a side View of the gun and a manifold therefor, showing the gun and its handle in section and the manifold in elevation.

Fig. 2 is a bottom view of the manifold.

Fig. 3 is a diagrammatic View of a complete spray gun system.

Referring now to the drawings, the device of the invention in its preferred form comprises a gun Iii, a handle I and a manifold I2. The gun I comprises a tubular housing I3, co-axially of which is disposed a tubular member I4. The tube I4 is provided with a tapered ange or collar I5 to provide an airtight flt with the forward end of the housing, and at its rearward end it is threaded at I6 so as to be engageable with a nut I1 to clamp the tube firmly in the housing.

The tube I4 is provided with a central bore or duct 26 closed at its rearward end as shown and flared at its forward end at 21, and it is also provided with spaced annular flanges 28, 29 and 30 defining annular recesses 3l, 32 and 33. Longitudinal ducts 34 are provided as shown, and radial ducts 35 are provided communicating the annular recess 3| with the ducts 34. Radial ducts 3 communicate the annular recess 33 with the central duct 2B. A sleeve 31 is provided, being threaded to the tube I4 and forming an annular passage 38 communicating with the ducts 34.

As shown, the forward end of the tube I4 is grooved to provide longitudinal grooves or passages 39, and the sleeve 31 is of reduced inside diameter at its forward end at 4U so as to pro- Vide an annular shoulder 4I disposed slightly forwardly of the rear ends of the grooved section 39. Thus .the annular passage 38 is in effect continued but is caused to change its course for a purpose explained hereinafter.

Thek handle portion II of the gun assembly comprises mating portions 48, of which only one is shown, clamped together by means of screws 49. Disposed within the handle are tubes 50, 5I and 52 communicating at their upper ends with the ducts 45, 45 and41, respectively, and at their lower ends with the manifold I2, coupling members 53 beingv employed with the tubes 5I and 52, as shown.

The manifold I2 may be of any suitable type, but preferably it is of the type described in our copending application Serial No. 51,426, filed September 27, 1948, entitled Spraying device and manifold therefor which may be consulted for details. Briey, the manifold I2 comprises a block 54 which is provided with valves and coupling members as shown, and with internal ducts (not shown). An air inlet coupling 55 is provided for entry of compressed air, an. air outlet coupling 56, air control valves 51 and 58, an inlet coupling 59, combustible gas and oxygen inlet couplings and 6I, respectively, and valves 62 and @3 for controlling combustible gas and oxygen, respectively.

As explained in greater detail in the aforesaid copending application, by closing the valve 51 and opening the valve 58, all of the compressed air is directed to the outlet 5B, and by closing the valve 58 and opening the valve 51, all of the air is directed to the tube 50, thence to the gun I0. By appropriately adjusting the valves 51 and 58, any desired proportion of air is directed to the outlet 55 or to the tube 50. Referring to Fig. 3, there is shown a spray gun system, including the gun Il), handle II and manifold I2. Combustible gas and oxygen enter through ducts 1G and 1I, respectively, under control of valves 62 and 63. Compressed air enters through a duct 1'2, and by manipulation of valves 51 and 58, any desired proportion is sent directly to the gun through tube 50 or through a tube 13 to a dispenser or agitator 14 (where a dust is picked up), thence through a duct 15 and the manifold I2 to the tube 50 and the gun.

It will thus be apparent that a, spray gun, and a spray gun system, are provided which are of compact, simple design. Thus, all of the controls (for air, dust, combustible gas and oxygen) are brought together within a small compass adjacent the handle of the gun. All of the supply tubes lead through the handle er the gun, thus obviating the awkwardness of supply lines entering at the rear of the gun. The oiset passage for combustible gas and oxygen formed by the annular passage 38, grooves 39 and shoulder 4| create a turbulence which enhances the efficiency of combustion thus saving substantially in consumption of oxygen.

While we have shown the preferred form of our invention, it is to be understood that various changes may be made in its construction by those skilled in the art without departing from the spirit of the invention as defined in the appended claims.

Having thus described our invention, whatwe claim and desire to secure by Letters Patent is:

1. A spray gun comprising an inner tubular member adapted to deliver a suspension of solid material in air, said inner tubular member being provided with a plurality of axially disposed grooves at its outer end and on its exterior surface, said grooves terminating at the outer end of said inner tubular member, and an outer tubular member concentrically disposed with respect to said inner tubular member and spaced therefrom to provide an annular passage for combustible gas and oxygen, said outer tubular member being of lesser inside diameter at its forward end adjacent the grooved portion of said inner tubular member so as to provide an annular shoulder and an oiset continuation of said annular passage.

2. A spray gun comprising an inner tubular member adapted to deliver a suspension of solid material in air and having at its forward end a plurality of axial grooves formed on its exterior surface and terminating at its outer end, and an outer tubular member spaced from said inner y tubular member to provide an annular passage for delivery of combustible gas and oxygen, the said outer tubular member being of lesser inside diameter at its outer end to provide an annular shoulder and an offset continuation of said annular passage.

3. A spray gun comprising an inner tubular member defining an axial passage for a suspension of solid material in air, an outer tubular member disposed at the forward portion of said inner member and defining therewith an annular passage for combustible gas and oxygen, a

tubular housing for the rearward portion of said inner member, and a handle secured to said housing, said handle having separate ducts for suspension, combustible gas and oxygen formed therein, said inner member having axially spaced, annular anges forming a close t with and spacing, the inner member from said housing and sealing the outlet ends of said ducts from one another, said inner member being formed with a mixing chest communicating with said annular passage and with said gas and oxygen ducts, said inner member also being provided with a passage communicating said suspension duct with said axial passage.

4. A spray gun comprising an inner tubular member defining an axial passage for a suspension of solid material in air, an outer tubular member disposed at the forward portion of said inner-member and defining therewith an annular passage for combustible gas and oxygen, a tubular housing for the rearward portion of said inner member, a handle secured to said housing, said handle having separate ducts for suspension, combustible gas and oxygen formed therein, axially spaced, annular sealing members spacing the inner member from said housing and sealing the outlet ends of said ducts from one another, said inner member being formed with a mixing chest communicating with said annular passage and with said gas and oxygen ducts, said inner member also being provided with a passage communicating said suspension duct with said axial passage.

MANUEL A. SANDORA. CECIL E. FREEMAN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,781,603 Schori Nov. 11, 1930 2,227,753 Ingham Jan. 7, 1941 2,397,165 Shepard Mar. 26, 1946 2,414,181 Vandersee Jan. 14, 1947 FOREIGN PATENTS Number Country Date 738,881 France Dec. 20, 1932 

